I have been working at this for about an hour now. I've looked at other questions n this sight with the exact same error and I tried there solutions. I am still getting the error though. Here is my code:
class Links: UIViewController {
let firstLinkButton: UIButton?
let secondLinkButton: UIButton?
#IBAction func firstLinkButton(sender: AnyObject) {
UIApplication.sharedApplication().openURL(NSURL(string: "http://www.google.com")!)
}
#IBAction func secondLinkButton(sender: AnyObject) {
UIApplication.sharedApplication().openURL(NSURL(string: "http://www.bing.com")!)
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
This is probably the simplest question on this sight today but any input or suggestions are greatly appreciated. Thanks in advance.
P.S.: R.I.P. my reputation.
Make the buttons var
var firstLinkButton: UIButton?
var secondLinkButton: UIButton?
let constants must be initialized instantly.
Related
hey guys just wondering if you could help me debug this, this error comes up but only when i add a ui text view to a view controller here is everything i have for the view controller code as you can see i tried dispatchQueue but doesn't do anything.
import UIKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
DispatchQueue.main.async {
weak var textview: UITextView!
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
Declare variable out side the viewDidLoad
import UIKit
class ViewController: UIViewController {
var textview: UITextView!
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
It looks like you're working with this controller from not-main thread. I think that you're trying to show the controller from some closure or async call. You have to ensure that your UI calls only from main thread.
Also you can debug it. Before you create/instantiate this controller set breakpoint and pay attention on debug navigator in XCode, you will be able to see where the program stopped, is this main thread or not.
I haven't done much iOS development in a while and while updating an old project I came across a question I couldn't find an answer for.
What is the replacement for
actionSheet:willDismissWithButtonIndex:
(emphasis on WILL)
I have some animation code that needs to execute at this point and currently I can only see how to execute my code after the sheet has been dismissed.
I'm sure the answer is right in front of my face, I just can't see it.
You can create a custom UIAlertController with a delgate and use that
import UIKit
#objc protocol CustomAlertControllerDelegate {
#objc optional func CustomAlertControllerWillDismiss(controller: CustomAlertController)
}
class CustomAlertController: UIAlertController {
weak var delegate:CustomAlertControllerDelegate?
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
self.delegate?.CustomAlertControllerWillDismiss!(controller: self)
}
}
How do I reveal the passcode dots in swift, so then the user can see their password by clicking a button.
Thanks
Tyge
TextField has a property called secureTextEntry. All you need is to connect an outlet to your textfield and toggle secureTextEntry:
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var passwordField: UITextField!
override func viewDidLoad() {
super.viewDidLoad()
passwordField.secureTextEntry = true
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func showHide(sender: UIButton) {
passwordField.secureTextEntry = !passwordField.secureTextEntry
sender.setTitle({passwordField.secureTextEntry ? "Show":"Hide"}(), forState: .Normal)
}
}
stackoverflow provides a working search engine, but anyway here you is the answer.
Do the same, but with false instead of true
Obscure a UITextField password
By the way make sure that the user knows what he does when reveal the secure text.
Passing only input text from textfield to label in second VC works!! But i want when user type number 10 in uitextfield, ( 1 ticket is 2 euros so 10 tickets * 2 euro is 20) and when i click PAY button, so that SUM can be displayed in label in second VC, i think that viewdidload in VC2 is happening before prepareForSegue, i don't know. It works when i click second time on PAY button, but not when i first click PAY button where label displays zero, help :) Embedded in navigation controller for navigation.
VC1
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var howManyTickets: UITextField!
var sumTicketsAndPriceOfTickets = Int()
var priceOfTicket = 2 // euros
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func platiTeKarte(sender: AnyObject) {
sumTicketsAndPriceOfTickets = howManyTickets.text.toInt()! * priceOfTicket
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
let driver = segue.destinationViewController as! primaocViewController
var whatToPass = sumTicketsAndPriceOfTickets
driver.receiver = whatToPass
}
}
VC2
import UIKit
class primaocViewController: UIViewController {
#IBOutlet weak var displaySum: UILabel!
var receiver:Int!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
self.displaySum.text = String(receiver)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
If your button is wired directly to a segue, then you don't need an #IBAction as well. As you are seeing, the prepareForSegue is happening before the #IBAction for your Pay button. Just compute your value in prepareForSegue:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
let driver = segue.destinationViewController as! primaocViewController
driver.receiver = (howManyTickets.text.toInt() ?? 0) * priceOfTicket
}
I changed the calculation of the pay to use the nil coalescing operator ??. This is generally a safer approach because if the toInt() returns nil for any reason, it will in this case just use 0 instead of crashing.
I'm a beginner at all of this...Having said that I've come across a point in my app where I've stalled and don't know what to do or fix next. So any answers would be appreciated!
So in my Home View Controller, I have four buttons with four different categories.
Each of these categories has its own question list, but they have a common "General Question" list. The general question list has its own view controller.
When you click on any of the four buttons, it brings you to the General Question view. At the bottom of this view, I have a "Next" button.
Goal: Configure the Next button to continue to one of the category's question list based on what is initially pressed in the Home View Controller.
I've connected the buttons via outlet and action in the View Controller.
However, the Next button will not connect when I control + drag into the View Controller. I'm not sure where I need to put the code for this...
I was thinking that the code for the Next button might need to have some kind of conditional statement, but since it won't connect I can't even get that far.
Help!
(This is what I have) Sample Code:
import UIKit
import AddressBookUI
import AddressBook
import Foundation
import CoreData
import CoreGraphics
import EventKit
import EventKitUI
import CoreFoundation
class ViewController: UIViewController {
#IBOutlet var ColorButton: UIButton!
#IBOutlet var StyleButton: UIButton!
#IBOutlet var CutButton: UIButton!
#IBOutlet var MakeupButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
var eventstore: EKEventStore!
var event: EKEvent!
weak var editViewDelegate: EKEventEditViewDelegate!
#IBAction func ColorButtonPressed(sender: UIButton) {
}
#IBAction func StyleButtonPressed(sender: UIButton) {
}
#IBAction func HaircutButtonPressed(sender: UIButton) {
}
#IBAction func MakeupButtonPressed(sender: UIButton) {
}
}
Here is a suggested approach as shown in the code below for 2 controllers (instead of 4) for brevity. Use appropriate named segues to each of the "next processing" controllers from the common processing controller and set up a chain. Here is a link to the project file: Project file
import UIKit
class ViewController: UIViewController {
var nextVcId = 0 // defines the button that is pressed
#IBAction func unwindFromOtherControllers(segue: UIStoryboardSegue) {
// In case you want to get back to the main VC
}
#IBAction func btn2Action(sender: UIButton) {
nextVcId = 0
self.performSegueWithIdentifier("commonSegue", sender: sender)
}
#IBAction func btn1Action(sender: UIButton) {
nextVcId = 1
self.performSegueWithIdentifier("commonSegue", sender: sender)
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
let vc = segue.destinationViewController as! CommonViewController
vc.nextControllerId = nextVcId
}
}
import UIKit
class CommonViewController: UIViewController {
var nextControllerId = 0
#IBOutlet weak var StatusLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
self.StatusLabel.text = "Common"
commonProcessing()
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func commonProcessing() {
// do your common processing
if nextControllerId == 0 {
performSegueWithIdentifier("next1Segue", sender: self)
} else {
performSegueWithIdentifier("next2Segue", sender: self)
}
}
}
import UIKit
class Next1ViewController: UIViewController {
#IBOutlet weak var statusLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
self.statusLabel.text = "Next1"
next1Processing()
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func next1Processing() {
println("Next 1 Processing")
}
}
import UIKit
class Next2ViewController: UIViewController {
#IBOutlet weak var statusLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
statusLabel.text = "Next 2"
next2Processing()
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func next2Processing() {
println("Next 2 Processing")
}
}
processing